Randomised controlled trial of weekly chloroquine to re-establish normal erythron iron flux and haemoglobin recovery in postmalarial anaemia

OBJECTIVE

To determine if low-dose weekly chloroquine (CQ) therapy improves recovery from malaria-associated anaemia.

DESIGN

Proof of concept randomised clinical trial.

SETTING

West Kiang District, Lower River Region, The Gambia.

PARTICIPANTS

Children resident in participating communities, aged 12-72 months, with uncomplicated malaria identified using active case detection over two consecutive malaria transmission seasons.

INTERVENTIONS

In 2007, eligible children were randomised to chloroquine-sulfadoxine/pyrimethamine (CQ-SP) or co-artemether (ACT) antimalarial therapy, and after parasite clearance on day 3 were subsequently re-randomised (double-blind) to weekly low-dose CQ (5 mg/kg) or placebo. In 2008, all eligible children were treated with ACT and subsequently randomised to CQ or placebo.

OUTCOME MEASURES

The primary outcome was a change in haemoglobin from baseline (day 3 of antimalarial treatment) to day 90 in the CQ and placebo treatment arms. Secondary outcomes were changes in urinary neopterin as a marker of macrophage activation, markers of erythropoietic response and prevalence of submicroscopic parasitaemia. Change in haemoglobin in the placebo arm by initial antimalarial treatment was also assessed.

RESULTS

In 2007, 101 children with uncomplicated malaria were randomised to antimalarial treatment with CQ-SP or ACT and 65 were subsequently randomised to weekly CQ or placebo. In 2008, all children received ACT antimalarial treatment and 31 were subsequently randomised to receive weekly CQ or placebo. Follow-up to day 90 was 96%. There was no effect of weekly CQ vs placebo on change in haemoglobin at day 90 (CQ+10.04 g/L (95% CI 6.66 to 13.42) vs placebo +7.61 g/L (95% CI 2.88 to 12.35)). There was no effect on the secondary outcomes assessed, or effect of initial antimalarial therapy on haemoglobin recovery. Higher day 90 haemoglobin correlated independently with older age, not being stunted, higher haemoglobin at day 0 and adequate iron status at day 3.

CONCLUSIONS

Weekly low-dose CQ after effective antimalarial treatment is not effective in improving recovery from postmalarial anaemia.

TRIAL REGISTRATION

The clinical trial registration number is NCT00473837 (ClinicalTrials.gov).

Helicobacter pylori infection and circulating ghrelin levels - a systematic review

BACKGROUND

The nature of the association between ghrelin, an orexigenic hormone produced mainly in the stomach, and Helicobacter pylori (H pylori), a bacterium that colonises the stomach, is still controversial. We examined available evidence to determine whether an association exists between the two; and if one exists, in what direction.

METHODS

We reviewed original English language studies on humans reporting circulating ghrelin levels in H pylori infected and un-infected participants; and circulating ghrelin levels before and after H pylori eradication. Meta-analyses were conducted for eligible studies by combining study specific estimates using the inverse variance method with weighted average for continuous outcomes in a random effects model.

RESULTS

Seventeen out of 27 papers that reported ghrelin levels in H pylori positive and negative subjects found lower circulating ghrelin levels in H pylori positive subjects; while 10 found no difference. A meta-analysis of 19 studies with a total of 1801 participants showed a significantly higher circulating ghrelin concentration in H pylori negative participants than in H pylori positive participants (Effect estimate (95%CI) = -0.48 (-0.60, -0.36)). However, eradicating H pylori did not have any significant effect on circulating ghrelin levels (Effect estimate (95% CI) = 0.08 (-0.33, 0.16); Test for overall effect: Z = 0.67 (P = 0.5)).

CONCLUSIONS

We conclude that circulating ghrelin levels are lower in H pylori infected people compared to those not infected; but the relationship between circulating ghrelin and eradication of H pylori is more complex.

Helicobacter pylori infection and circulating ghrelin levels - a systematic review

Background

The nature of the association between ghrelin, an orexigenic hormone produced mainly in the stomach, and Helicobacter pylori (H pylori), a bacterium that colonises the stomach, is still controversial. We examined available evidence to determine whether an association exists between the two; and if one exists, in what direction.

Methods

We reviewed original English language studies on humans reporting circulating ghrelin levels in H pylori infected and un-infected participants; and circulating ghrelin levels before and after H pylori eradication. Meta-analyses were conducted for eligible studies by combining study specific estimates using the inverse variance method with weighted average for continuous outcomes in a random effects model.

Results

Seventeen out of 27 papers that reported ghrelin levels in H pylori positive and negative subjects found lower circulating ghrelin levels in H pylori positive subjects; while 10 found no difference. A meta-analysis of 19 studies with a total of 1801 participants showed a significantly higher circulating ghrelin concentration in H pylori negative participants than in H pylori positive participants (Effect estimate (95%CI) = -0.48 (-0.60, -0.36)). However, eradicating H pylori did not have any significant effect on circulating ghrelin levels (Effect estimate (95% CI) = 0.08 (-0.33, 0.16); Test for overall effect: Z = 0.67 (P = 0.5)).

Conclusions

We conclude that circulating ghrelin levels are lower in H pylori infected people compared to those not infected; but the relationship between circulating ghrelin and eradication of H pylori is more complex.

Haptoglobin genotype, anaemia and malaria in Gambian children

OBJECTIVE

To retest our previous finding that the haptoglobin (Hp) 22 genotype is associated with seasonal anaemia, and to investigate the role of malaria in this effect.

METHODS

Haemoglobin (Hb) and peripheral parasitaemia were assessed at pre- and post-malarial season cross-sectional surveys in rural Gambian children aged 10-72 months. Between the surveys, active longitudinal surveillance was conducted to detect febrile episodes.

RESULTS

Unlike previously, no overall reduction in Hb was observed (Hb = 106.1 vs. 107.2 g/l, P = 0.13, n = 545). However, multi-variable linear regression revealed differences in Hb over the season by Hp and Hb-sickle (HbS) genotype (-2.20 g/l per copy of the Hp2 allele, P = 0.043; HbAS vs. HbAA + 3.13 g/l, P = 0.11, n = 536). There was no effect of malarial episodes during follow-up; this suggests that when effective treatment is given, Hb levels recover. The A61-C Hp promoter SNP, associated with the Hp2 allele, had no effect.

CONCLUSION

The effect of the Hp2 allele appears to be independent of effects on malaria incidence but may affect Hb levels through increased oxidant stress and red cell turnover. This may be supported by our previous observations that the effect of Hp22 was independent of markers of iron status and zinc protoporphyrin measured at the cross-sectional surveys and therefore also of iron availability for erythropoiesis.

Sexual practices of church youths in the era of HIV/AIDS: Playing the ostrich

The church could be a powerful force for social and behavioural change, particularly in the current efforts to combat the HIV/AIDS pandemic. Anecdotal evidence suggests that church youths are sexually active but few studies have documented the sexual practices of these youths. We looked at the sexual practices of 341 youths in two churches in southern Nigeria. Sixty-five percent were sexually experienced; age at first sexual intercourse for males was seven years and eight years for females. By 19 years of age, 42% of the females and 44% of the males had become sexually active. In the 12 months preceding the study, 19% of the sexually experienced youths abstained from sex, 30% had one sexual partner and 28% had more than one sexual partner; 60% had used condoms 24% of whom used them always. These results suggest that sexual practices of committed church youths might be similar to those of youths in the wider society. More might be achieved by a more pro-active engagement of the church in young people's sexual and reproductive health matters.

Haplotype association between haptoglobin (Hp2) and Hp promoter SNP (A-61C) may explain previous controversy of haptoglobin and malaria protection

Background

Malaria is one of the strongest recent selective pressures on the human genome, as evidenced by the high levels of varying haemoglobinopathies in human populations–despite the increased risk of mortality in the homozygous states. Previously, functional polymorphisms of Hp, coded by the co-dominant alleles Hp1 and Hp2, have been variously associated with several infectious diseases, including malaria susceptibility.

Methodology/Principal Findings

Risk of a clinical malarial episode over the course of a malarial transmission season was assessed using active surveillance in a cohort of Gambian children aged 10–72 months. We report for the first time that the major haplotype for the A-61C mutant allele in the promoter of haptoglobin (Hp)–an acute phase protein that clears haemoglobin released from haemolysis of red cells–is associated with protection from malarial infection in older children, (children aged ≥36 months, >500 parasites/ul and temperature >37.5°C; OR = 0.42; [95% CI 0.24–0.73] p = 0.002) (lr test for interaction, <36 vs ≥36 months, p = 0.014). Protection was also observed using two other definitions, including temperature >37.5°C, dipstick positive, plus clinical judgement of malaria blinded to dipstick result (all ages, OR = 0.48, [95% CI 0.30–0.78] p = 0.003; ≥36 months, OR = 0.31, [95% CI 0.15–0.62] p = 0.001). A similar level of protection was observed for the known protective genetic variant, sickle cell trait (HbAS).

Conclusions/Significance

We propose that previous conflicting results between Hp phenotypes/genotypes and malaria susceptibility may be explained by differing prevalence of the A-61C SNP in the populations studied, which we found to be highly associated with the Hp2 allele. We report the -61C allele to be associated with decreased Hp protein levels (independent of Hp phenotype), confirming in vitro studies. Decreased Hp expression may lead to increased oxidant stress and increased red cell turnover, and facilitate the development of acquired immunity, similar to a mechanism suggested for sickle cell trait.

Acceptability of female-controlled HIV/STI prevention options by Nigerian professionals - an exploratory study

The attitudes of working professionals, particularly in the healthcare sector, may play a large role in the acceptance or otherwise of female-controlled HIV/STI prevention options. In 2002, we conducted an exploratory study on the perceptions surrounding female-controlled HIV/STI prevention options, principally the acceptability of a female condom or a vaginal microbicide, among a small sample of Nigerian professionals. A self-administered structured questionnaire was given to 50 persons representing four professions. The majority of the respondents agreed with a proposition stating a need for female-controlled HIV/STI prevention options. More females than males supported such options; both male and female respondents expressed a higher preference for a vaginal microbicide than for the female condom. The reasons given for unwillingness to use the female condom included social, cultural and religious biases, cumbersomeness and inefficiency. Only a small proportion of the total respondents felt willing to participate in a clinical trial with the vaginal microbicide. Further studies are needed to determine the relevance of these findings to the professional community in Nigeria at large, especially for the purposes of planning better social marketing strategies.

Malaria parasitaemia in neonates in Port Harcourt, Nigeria

Malaria is thought to be rare among neonates in malaria-endemic regions. Consequently, blood film for malaria parasite is not routinely included in the sepsis screening protocol for neonates. We examined the role of malaria in perinatal morbidity among neonates admitted into our unit with a view to determining the need or otherwise of including malaria parasitaemia in the sepsis work-up in suspected neonatal septicaemia. Fourteen babies who met our preset criteria were screened for malaria parasitaemia out of which five (35.71 per cent) had positive blood smears for Plasmodium falciparum. Eighty per cent of the neonates presenting with fever had positive blood films (Yates corrected chi2 = 3.9822; p = 0.04). All the babies responded to an oral course of chloroquine. These data have further highlighted the importance of malaria in perinatal morbidity in our environment. We recommend a multi-centred study to define clearly the role of malaria in perinatal and neonatal morbidity and mortality in malaria endemic areas.